*{
    margin: 0;
    padding: 0;
}
.dhz{
    background: black;
    width: 1357px;
    height: 838px;
    margin: auto;
}
.sbjt{
    width: 1000px;
    height: 400px;
    background-image: url(../作业/images/top-bg.gif);
    margin: auto;
    position: relative;
}
.zbjt{
    width: 1000px;
    height: 290px;
    background-image: url(../作业/images/cont-box-top.gif);
    margin: auto;
    position: relative;
    z-index: 1;
}
.xbjt{
    width: 1000px;
    height: 80px;
    background-image:url(../作业/images/bottom-bg.gif);
    margin: auto;
}
.dhz>.sbjt>img:nth-child(2){
    left: 284px;
    top: 84px;
    position: absolute;
}
.dhz>.sbjt>img:nth-child(3){
    top: 84px;
    position: absolute;
    left: 529px;
}
.dhz>.sbjt>img:nth-child(4){
    position: absolute;
    top: 84px;
    left: 770px;
}
ul{
    position: relative;
    left: 284px;
    top: -200px;
}
ul>li{
    float: left;
    list-style: none;
    color: white;
    margin-right: 77px;
}
ul>li:nth-child(1){
    color: red;
}
.swz{
    margin-left: 31px;
    color: white;
}
.swz>p{
    font-size: 13px;
}
.h1{
    margin-right: 600px;
    width: 500px;
}
.zbjt>img:nth-child(1){
    position: absolute;
    left: 580px;
}
.zbjt>h1{
    position: absolute;
    left: 31px;
    top: 31px;
}
.dyd{
    position: absolute;
    left: 31px;
    top: 94px;
}
.ded{
    position: absolute;
    left: 31px;
    top: 164px;
}
.dsd{
    position: absolute;
    left: 31px;
    top: 240px;
}
.dydwz{
    color: white;
    width: 458px;
    height: 50px;
    position: absolute;
    top: 93px;
    font-size: 13px;
    left: 110px;
}
.dedwz{
    position: absolute;
    
    color: white;
    width: 458px;
    height: 50px;
    font-size: 13px;
    left: 110px;
    top: 163px;
}
.dsdwz{
    position: absolute;
    top: 238px;
    color: white;
    width: 458px;
    height: 50px;
    font-size: 13px;
    left: 110px;
}
a{
    color: white;
}
.xbjt{
    color: white;
    position: relative;
    z-index: 0;
}
.xbjt>div{
    margin-top: 70px;
    position: absolute;
    font-size: 13px;
}
.zb{
    width: 300px;
    margin-top: 20px;
    position: absolute;
}
.yb{
    width: 800px;
    margin-left: 300px;
    position: absolute;
    top: 20px;
}
